From: Simon Horman <horms@kernel.org>
To: Jinjie Ruan <ruanjinjie@huawei.com>
Cc: netdev@vger.kernel.org,
Florian Fainelli <florian.fainelli@broadcom.com>,
Andrew Lunn <andrew@lunn.ch>, Vladimir Oltean <olteanv@gmail.com>,
"David S. Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
Vivien Didelot <vivien.didelot@gmail.com>
Subject: Re: [PATCH v3] net: dsa: bcm_sf2: Fix possible memory leak in bcm_sf2_mdio_register()
Date: Fri, 13 Oct 2023 13:46:41 +0200 [thread overview]
Message-ID: <20231013114641.GG29570@kernel.org> (raw)
In-Reply-To: <20231011032419.2423290-1-ruanjinjie@huawei.com>
On Wed, Oct 11, 2023 at 11:24:19AM +0800, Jinjie Ruan wrote:
> In bcm_sf2_mdio_register(), the class_find_device() will call get_device()
> to increment reference count for priv->master_mii_bus->dev if
> of_mdio_find_bus() succeeds. If mdiobus_alloc() or mdiobus_register()
> fails, it will call get_device() twice without decrement reference count
> for the device. And it is the same if bcm_sf2_mdio_register() succeeds but
> fails in bcm_sf2_sw_probe(), or if bcm_sf2_sw_probe() succeeds. If the
> reference count has not decremented to zero, the dev related resource will
> not be freed.
>
> So remove the get_device() in bcm_sf2_mdio_register(), and call
> put_device() if mdiobus_alloc() or mdiobus_register() fails and in
> bcm_sf2_mdio_unregister() to solve the issue.
>
> And as Simon suggested, unwind from errors for bcm_sf2_mdio_register() and
> just return 0 if it succeeds to make it cleaner.
>
> Fixes: 461cd1b03e32 ("net: dsa: bcm_sf2: Register our slave MDIO bus")
> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
> Suggested-by: Simon Horman <horms@kernel.org>
Thanks, this addresses my concerns around v2.
Reviewed-by: Simon Horman <horms@kernel.org>
next prev parent reply other threads:[~2023-10-13 11:46 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-10-11 3:24 [PATCH v3] net: dsa: bcm_sf2: Fix possible memory leak in bcm_sf2_mdio_register() Jinjie Ruan
2023-10-13 11:46 ` Simon Horman [this message]
2023-10-13 16:12 ` Florian Fainelli
2023-10-13 23:40 ` patchwork-bot+netdevbpf
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